The present invention is directed to the general field of dynamically balancing the wheel assemblies found on automobiles, trucks, airplanes, and other vehicles by introducing a predetermined amount of a pulverulent material, such as a product sold under the trademark EQUAL.RTM. by International Marketing, Inc. of Chambersburg, Pa., into a pneumatic tire which is mounted on a wheel or rim of the wheel assembly. As used herein, the terms "wheel assembly" and "tire assembly" each refer to a tire mounted on a wheel or a rim.
The specifics of the method of balancing a wheel assembly (including equalizing radial and lateral force variations) by introducing a pulverulent material into the tire thereof are fully disclosed in U.S. Pat. No. 5,073,217 issued to Robert D. Fogal on Dec. 17, 1991, all of which patent is also expressly incorporated by reference herein. As is described in U.S. Pat. No. 5,472,023, introducing pulverulent material into a tire of a wheel assembly generally involves confining a predetermined amount of pulverulent material; subjecting the confined pulverulent material to pressurized air currents; and, introducing the pulverulent material into a tire through an associated tire valve stem under the force of the pressurized air currents. This prior patent also describes two different applicator devices for performing the above method. While these devices are effective in carrying out these operations, they require the operator thereof to perform a variety of time consuming manual steps. For example, once the operator determines the proper amount of pulverulent material to be utilized within a tire, the operator must manually dispense this predetermined amount (typically in terms of weight) and place the same within the cylinder of the applicator device. The applicator device must then be sealed and connected between the tire valve stem of the wheel assembly and a source of compressed air such as a shop air line. Once the applicator device is properly connected, the operator must manually open one or more valves to allow compressed air to flow into the applicator and an admixture of compressed air and pulverulent material to exit the applicator and travel into the tire through the associated tire valve stem.
In addition to the above steps required of an operator during the application procedure, the operator must also perform a number of preliminary steps to prepare the tire to receive the pulverulent material. If the tire has just been mounted on a wheel or rim, the operator must first "bead" the tire--i.e., compressed air must be introduced into the tire to ensure that the bead of each sidewall is properly seated against its respective rim flange. Once a tire is beaded properly, it must be at least partially deflated so that it will not become overinflated upon the introduction of the compressed air and pulverulent material into the tire. An operator has heretofore been required to bead a newly mounted tire prior to connecting the valve stem of the wheel assembly to the applicator apparatus. Also, the operator has heretofore been required to deflate or "bleed" an already mounted tire in preparation for the application procedure. Only after these steps have been performed, was the operator able to connect the valve stem of the tire to the applicator device. Finally, prior applicator devices typically require the operator to disconnect the tire therefrom in order to complete the application procedure by inflating the tire to its recommended tire pressure.
There has therefore been found a need to provide an applicator apparatus and a method for introducing a pulverulent material into a tire without the above-noted deficiencies of prior applicator devices and methods. Specifically, there has been found a need to provide an applicator apparatus that performs the "beading" operation (if required), performs pre-application partial deflation of the tire (if required), introduces the pulverulent material into a tire, and performs the final re-inflation procedure. There has also been found a need to provide an apparatus that quickly and efficiently dispenses a predetermined amount of pulverulent material from a source thereof into a confining space in preparation for its "application" or introduction into a tire.